The present invention relates to an improved device for promoting hemostasis and/or wound healing, and an improved method for making said device.
WO 2003/004072 discloses a method for coating a medical appliance, such as a stent, with a bubblejet printing head. The coating may comprise pharmaceutically active compounds and may e.g. be in the form of a polymer with a suspended drug or a non-thrombogenic agent.
Xu et al (Biomaterials Vol. 27, 2006, p. 3580-3588) discloses use of alternate inkjet printing of NT2 cells and fibrin gels (formed by the alternate printing of fibrinogen and thrombin), to create 3D cellular structures consisting of layers of neural cells.
U.S. Pat. Nos. 6,361,551 and 6,454,787 both relate to methods for depositing thrombin in solution or powder onto a hemostatic device, such as a sponge comprising collagen. The method of depositing thrombin comprises spraying thrombin in powder form onto the hemostatic device, or coating the device with a thrombin solution and subsequently drying the device of the invention by lyophilization or by conventional means.
U.S. Pat. No. 4,752,466 is directed to a thrombin aerosol. Thrombin is delivered in dry powdered form from a valve-actuated pressurized propellant-containing aerosol container. The thrombin has been lyophilized from an aqueous solution also comprising a thrombin-compatible synthetic polymer.
U.S. Pat. Nos. 6,472,162 and 7,056,722 both concern a thrombin-solution without particles. The particles have been removed by filtration so as to allow using the thrombin-solution as a spray.
U.S. Pat. No. 6,461,325 relates to a device for delivering fibrin and forming fibrin on a surface. The device delivers volumetric quantities of a first and a second biochemically reactive fluid comprising a spray unit for separately atomizing the first and second biochemically reactive fluids into an aerosol. The first or second biochemically reactive fluids may comprise thrombin.
U.S. Pat. No. 6,113,948 relates to soluble microparticles comprising thrombin or fibrinogen in free-flowing form. The microparticles can be mixed to give a dry powder to be used as a fibrin sealant that is activated only at a wound site. The microparticles are produced by spray-drying.
US 2003/0175419 relates to methods for preparing biomimetic scaffolds by using at least two bio-ink solutions. The bio-ink solutions can be deposited individually or simultaneously. One bio-ink, which is structural, can comprise thrombin, and inkjet technology can be employed to deposit the bio-inks of the biomimetic scaffold. Another form of a bio-ink can comprise gelatin.
U.S. Pat. No. 6,416,739 discloses microcapsules comprising thrombin for therapeutic use.
U.S. Pat. No. 6,649,162 is related to a hemostatic sponge based on collagen and thrombin and a method for producing such a sponge as well as a wound coverage containing said sponge. Thrombin is homogenously distributed in the sponge.
The prior art has not addressed sufficiently the issue of providing an improved matrix material, such as a sponge, comprising a pharmaceutical composition comprising one or more agents or bioactive agents, such as thrombin; wherein said composition is initially in fluid or liquid form and applied onto the surface of said matrix material by printing the fluid or liquid composition in individual and discrete locations onto the surface of the matrix material, thus obtaining an essentially uniform distribution of said fluid or liquid composition.
The printing technology according to the present invention allows for a more precise distribution of the composition onto the surface of the matrix material by applying an amount of the fluid or liquid composition which preferably prevents swelling of the matrix material. The invention avoids waste of fluid or liquid composition by exploiting the printing technology's more precise distribution of the fluid or liquid composition onto the matrix material. Compared to conventional techniques in the art, such as spraying, a more uniform distribution of the composition is also achieved.